]>
Commit | Line | Data |
---|---|---|
ab31523c GH |
1 | /****************************************************************************** |
2 | * gntdev.c | |
3 | * | |
4 | * Device for accessing (in user-space) pages that have been granted by other | |
5 | * domains. | |
6 | * | |
7 | * Copyright (c) 2006-2007, D G Murray. | |
8 | * (c) 2009 Gerd Hoffmann <kraxel@redhat.com> | |
1d314567 | 9 | * (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc. |
ab31523c GH |
10 | * |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
19 | */ | |
20 | ||
21 | #undef DEBUG | |
22 | ||
283c0972 JP |
23 | #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt |
24 | ||
ee7f5225 | 25 | #include <linux/dma-mapping.h> |
ab31523c GH |
26 | #include <linux/module.h> |
27 | #include <linux/kernel.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/miscdevice.h> | |
30 | #include <linux/fs.h> | |
ab31523c GH |
31 | #include <linux/uaccess.h> |
32 | #include <linux/sched.h> | |
6e84f315 | 33 | #include <linux/sched/mm.h> |
ab31523c GH |
34 | #include <linux/spinlock.h> |
35 | #include <linux/slab.h> | |
aab8f11a | 36 | #include <linux/highmem.h> |
c5f7c5a9 | 37 | #include <linux/refcount.h> |
ab31523c GH |
38 | |
39 | #include <xen/xen.h> | |
40 | #include <xen/grant_table.h> | |
ca47ceaa | 41 | #include <xen/balloon.h> |
ab31523c | 42 | #include <xen/gntdev.h> |
bdc612dc | 43 | #include <xen/events.h> |
a9fd60e2 | 44 | #include <xen/page.h> |
ab31523c GH |
45 | #include <asm/xen/hypervisor.h> |
46 | #include <asm/xen/hypercall.h> | |
ab31523c | 47 | |
1d314567 | 48 | #include "gntdev-common.h" |
932d6562 OA |
49 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
50 | #include "gntdev-dmabuf.h" | |
51 | #endif | |
1d314567 | 52 | |
ab31523c GH |
53 | MODULE_LICENSE("GPL"); |
54 | MODULE_AUTHOR("Derek G. Murray <Derek.Murray@cl.cam.ac.uk>, " | |
55 | "Gerd Hoffmann <kraxel@redhat.com>"); | |
56 | MODULE_DESCRIPTION("User-space granted page access driver"); | |
57 | ||
3b06ac67 JG |
58 | static unsigned int limit = 64*1024; |
59 | module_param(limit, uint, 0644); | |
60 | MODULE_PARM_DESC(limit, | |
61 | "Maximum number of grants that may be mapped by one mapping request"); | |
ab31523c | 62 | |
aab8f11a DDG |
63 | static int use_ptemod; |
64 | ||
1d314567 OA |
65 | static int unmap_grant_pages(struct gntdev_grant_map *map, |
66 | int offset, int pages); | |
aab8f11a | 67 | |
975ef7ff OA |
68 | static struct miscdevice gntdev_miscdev; |
69 | ||
ab31523c GH |
70 | /* ------------------------------------------------------------------ */ |
71 | ||
3b06ac67 | 72 | bool gntdev_test_page_count(unsigned int count) |
1d314567 | 73 | { |
3b06ac67 | 74 | return !count || count > limit; |
1d314567 OA |
75 | } |
76 | ||
ab31523c GH |
77 | static void gntdev_print_maps(struct gntdev_priv *priv, |
78 | char *text, int text_index) | |
79 | { | |
80 | #ifdef DEBUG | |
1d314567 | 81 | struct gntdev_grant_map *map; |
ab31523c | 82 | |
ef91082e | 83 | pr_debug("%s: maps list (priv %p)\n", __func__, priv); |
ab31523c GH |
84 | list_for_each_entry(map, &priv->maps, next) |
85 | pr_debug(" index %2d, count %2d %s\n", | |
86 | map->index, map->count, | |
87 | map->index == text_index && text ? text : ""); | |
88 | #endif | |
89 | } | |
90 | ||
1d314567 | 91 | static void gntdev_free_map(struct gntdev_grant_map *map) |
a67baeb7 DV |
92 | { |
93 | if (map == NULL) | |
94 | return; | |
95 | ||
975ef7ff OA |
96 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
97 | if (map->dma_vaddr) { | |
98 | struct gnttab_dma_alloc_args args; | |
99 | ||
100 | args.dev = map->dma_dev; | |
101 | args.coherent = !!(map->dma_flags & GNTDEV_DMA_FLAG_COHERENT); | |
102 | args.nr_pages = map->count; | |
103 | args.pages = map->pages; | |
104 | args.frames = map->frames; | |
105 | args.vaddr = map->dma_vaddr; | |
106 | args.dev_bus_addr = map->dma_bus_addr; | |
107 | ||
108 | gnttab_dma_free_pages(&args); | |
109 | } else | |
110 | #endif | |
a67baeb7 | 111 | if (map->pages) |
ff4b156f | 112 | gnttab_free_pages(map->count, map->pages); |
975ef7ff OA |
113 | |
114 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC | |
b3f7931f | 115 | kvfree(map->frames); |
975ef7ff | 116 | #endif |
b3f7931f JG |
117 | kvfree(map->pages); |
118 | kvfree(map->grants); | |
119 | kvfree(map->map_ops); | |
120 | kvfree(map->unmap_ops); | |
121 | kvfree(map->kmap_ops); | |
122 | kvfree(map->kunmap_ops); | |
a67baeb7 DV |
123 | kfree(map); |
124 | } | |
125 | ||
1d314567 | 126 | struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count, |
975ef7ff | 127 | int dma_flags) |
ab31523c | 128 | { |
1d314567 | 129 | struct gntdev_grant_map *add; |
a12b4eb3 | 130 | int i; |
ab31523c | 131 | |
1d314567 | 132 | add = kzalloc(sizeof(*add), GFP_KERNEL); |
ab31523c GH |
133 | if (NULL == add) |
134 | return NULL; | |
135 | ||
f1d20d86 JB |
136 | add->grants = kvmalloc_array(count, sizeof(add->grants[0]), |
137 | GFP_KERNEL); | |
138 | add->map_ops = kvmalloc_array(count, sizeof(add->map_ops[0]), | |
139 | GFP_KERNEL); | |
140 | add->unmap_ops = kvmalloc_array(count, sizeof(add->unmap_ops[0]), | |
141 | GFP_KERNEL); | |
b3f7931f | 142 | add->pages = kvcalloc(count, sizeof(add->pages[0]), GFP_KERNEL); |
a12b4eb3 SS |
143 | if (NULL == add->grants || |
144 | NULL == add->map_ops || | |
145 | NULL == add->unmap_ops || | |
146 | NULL == add->pages) | |
ab31523c | 147 | goto err; |
36caa3fe | 148 | if (use_ptemod) { |
f1d20d86 JB |
149 | add->kmap_ops = kvmalloc_array(count, sizeof(add->kmap_ops[0]), |
150 | GFP_KERNEL); | |
151 | add->kunmap_ops = kvmalloc_array(count, sizeof(add->kunmap_ops[0]), | |
152 | GFP_KERNEL); | |
36caa3fe JB |
153 | if (NULL == add->kmap_ops || NULL == add->kunmap_ops) |
154 | goto err; | |
155 | } | |
ab31523c | 156 | |
975ef7ff OA |
157 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
158 | add->dma_flags = dma_flags; | |
159 | ||
160 | /* | |
161 | * Check if this mapping is requested to be backed | |
162 | * by a DMA buffer. | |
163 | */ | |
164 | if (dma_flags & (GNTDEV_DMA_FLAG_WC | GNTDEV_DMA_FLAG_COHERENT)) { | |
165 | struct gnttab_dma_alloc_args args; | |
166 | ||
b3f7931f JG |
167 | add->frames = kvcalloc(count, sizeof(add->frames[0]), |
168 | GFP_KERNEL); | |
975ef7ff OA |
169 | if (!add->frames) |
170 | goto err; | |
171 | ||
172 | /* Remember the device, so we can free DMA memory. */ | |
173 | add->dma_dev = priv->dma_dev; | |
174 | ||
175 | args.dev = priv->dma_dev; | |
176 | args.coherent = !!(dma_flags & GNTDEV_DMA_FLAG_COHERENT); | |
177 | args.nr_pages = count; | |
178 | args.pages = add->pages; | |
179 | args.frames = add->frames; | |
180 | ||
181 | if (gnttab_dma_alloc_pages(&args)) | |
182 | goto err; | |
183 | ||
184 | add->dma_vaddr = args.vaddr; | |
185 | add->dma_bus_addr = args.dev_bus_addr; | |
186 | } else | |
187 | #endif | |
ff4b156f | 188 | if (gnttab_alloc_pages(count, add->pages)) |
ca47ceaa DDG |
189 | goto err; |
190 | ||
a12b4eb3 | 191 | for (i = 0; i < count; i++) { |
f1d20d86 JB |
192 | add->grants[i].domid = DOMID_INVALID; |
193 | add->grants[i].ref = INVALID_GRANT_REF; | |
bce21a2b JB |
194 | add->map_ops[i].handle = INVALID_GRANT_HANDLE; |
195 | add->unmap_ops[i].handle = INVALID_GRANT_HANDLE; | |
36caa3fe | 196 | if (use_ptemod) { |
bce21a2b JB |
197 | add->kmap_ops[i].handle = INVALID_GRANT_HANDLE; |
198 | add->kunmap_ops[i].handle = INVALID_GRANT_HANDLE; | |
36caa3fe | 199 | } |
a12b4eb3 SS |
200 | } |
201 | ||
ab31523c GH |
202 | add->index = 0; |
203 | add->count = count; | |
c5f7c5a9 | 204 | refcount_set(&add->users, 1); |
ab31523c | 205 | |
ab31523c GH |
206 | return add; |
207 | ||
208 | err: | |
a67baeb7 | 209 | gntdev_free_map(add); |
ab31523c GH |
210 | return NULL; |
211 | } | |
212 | ||
1d314567 | 213 | void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add) |
ab31523c | 214 | { |
1d314567 | 215 | struct gntdev_grant_map *map; |
ab31523c GH |
216 | |
217 | list_for_each_entry(map, &priv->maps, next) { | |
218 | if (add->index + add->count < map->index) { | |
219 | list_add_tail(&add->next, &map->next); | |
220 | goto done; | |
221 | } | |
222 | add->index = map->index + map->count; | |
223 | } | |
224 | list_add_tail(&add->next, &priv->maps); | |
225 | ||
226 | done: | |
ab31523c GH |
227 | gntdev_print_maps(priv, "[new]", add->index); |
228 | } | |
229 | ||
1d314567 OA |
230 | static struct gntdev_grant_map *gntdev_find_map_index(struct gntdev_priv *priv, |
231 | int index, int count) | |
ab31523c | 232 | { |
1d314567 | 233 | struct gntdev_grant_map *map; |
ab31523c GH |
234 | |
235 | list_for_each_entry(map, &priv->maps, next) { | |
236 | if (map->index != index) | |
237 | continue; | |
bdc612dc | 238 | if (count && map->count != count) |
ab31523c GH |
239 | continue; |
240 | return map; | |
241 | } | |
242 | return NULL; | |
243 | } | |
244 | ||
1d314567 | 245 | void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map) |
ab31523c GH |
246 | { |
247 | if (!map) | |
248 | return; | |
a12b4eb3 | 249 | |
c5f7c5a9 | 250 | if (!refcount_dec_and_test(&map->users)) |
68b025c8 DDG |
251 | return; |
252 | ||
0cc678f8 | 253 | if (map->notify.flags & UNMAP_NOTIFY_SEND_EVENT) { |
bdc612dc | 254 | notify_remote_via_evtchn(map->notify.event); |
0cc678f8 DDG |
255 | evtchn_put(map->notify.event); |
256 | } | |
bdc612dc | 257 | |
a67baeb7 DV |
258 | if (map->pages && !use_ptemod) |
259 | unmap_grant_pages(map, 0, map->count); | |
260 | gntdev_free_map(map); | |
ab31523c GH |
261 | } |
262 | ||
263 | /* ------------------------------------------------------------------ */ | |
264 | ||
8b1e0f81 | 265 | static int find_grant_ptes(pte_t *pte, unsigned long addr, void *data) |
ab31523c | 266 | { |
1d314567 | 267 | struct gntdev_grant_map *map = data; |
ab31523c | 268 | unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT; |
aab8f11a | 269 | int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte; |
ab31523c GH |
270 | u64 pte_maddr; |
271 | ||
272 | BUG_ON(pgnr >= map->count); | |
ba5d1012 JF |
273 | pte_maddr = arbitrary_virt_to_machine(pte).maddr; |
274 | ||
923b2919 DV |
275 | /* |
276 | * Set the PTE as special to force get_user_pages_fast() fall | |
277 | * back to the slow path. If this is not supported as part of | |
278 | * the grant map, it will be done afterwards. | |
279 | */ | |
280 | if (xen_feature(XENFEAT_gnttab_map_avail_bits)) | |
281 | flags |= (1 << _GNTMAP_guest_avail0); | |
282 | ||
aab8f11a | 283 | gnttab_set_map_op(&map->map_ops[pgnr], pte_maddr, flags, |
ab31523c GH |
284 | map->grants[pgnr].ref, |
285 | map->grants[pgnr].domid); | |
aab8f11a | 286 | gnttab_set_unmap_op(&map->unmap_ops[pgnr], pte_maddr, flags, |
bce21a2b | 287 | INVALID_GRANT_HANDLE); |
ab31523c GH |
288 | return 0; |
289 | } | |
290 | ||
923b2919 | 291 | #ifdef CONFIG_X86 |
8b1e0f81 | 292 | static int set_grant_ptes_as_special(pte_t *pte, unsigned long addr, void *data) |
923b2919 DV |
293 | { |
294 | set_pte_at(current->mm, addr, pte, pte_mkspecial(*pte)); | |
295 | return 0; | |
296 | } | |
297 | #endif | |
298 | ||
1d314567 | 299 | int gntdev_map_grant_pages(struct gntdev_grant_map *map) |
ab31523c GH |
300 | { |
301 | int i, err = 0; | |
aab8f11a DDG |
302 | |
303 | if (!use_ptemod) { | |
12996fc3 | 304 | /* Note: it could already be mapped */ |
bce21a2b | 305 | if (map->map_ops[0].handle != INVALID_GRANT_HANDLE) |
12996fc3 | 306 | return 0; |
aab8f11a | 307 | for (i = 0; i < map->count; i++) { |
38eaeb0f | 308 | unsigned long addr = (unsigned long) |
aab8f11a DDG |
309 | pfn_to_kaddr(page_to_pfn(map->pages[i])); |
310 | gnttab_set_map_op(&map->map_ops[i], addr, map->flags, | |
311 | map->grants[i].ref, | |
312 | map->grants[i].domid); | |
313 | gnttab_set_unmap_op(&map->unmap_ops[i], addr, | |
bce21a2b | 314 | map->flags, INVALID_GRANT_HANDLE); |
aab8f11a | 315 | } |
0930bba6 SS |
316 | } else { |
317 | /* | |
318 | * Setup the map_ops corresponding to the pte entries pointing | |
319 | * to the kernel linear addresses of the struct pages. | |
320 | * These ptes are completely different from the user ptes dealt | |
321 | * with find_grant_ptes. | |
dbe52836 JB |
322 | * Note that GNTMAP_device_map isn't needed here: The |
323 | * dev_bus_addr output field gets consumed only from ->map_ops, | |
324 | * and by not requesting it when mapping we also avoid needing | |
325 | * to mirror dev_bus_addr into ->unmap_ops (and holding an extra | |
326 | * reference to the page in the hypervisor). | |
0930bba6 | 327 | */ |
dbe52836 JB |
328 | unsigned int flags = (map->flags & ~GNTMAP_device_map) | |
329 | GNTMAP_host_map; | |
330 | ||
0930bba6 | 331 | for (i = 0; i < map->count; i++) { |
0930bba6 SS |
332 | unsigned long address = (unsigned long) |
333 | pfn_to_kaddr(page_to_pfn(map->pages[i])); | |
0930bba6 SS |
334 | BUG_ON(PageHighMem(map->pages[i])); |
335 | ||
dbe52836 | 336 | gnttab_set_map_op(&map->kmap_ops[i], address, flags, |
0930bba6 SS |
337 | map->grants[i].ref, |
338 | map->grants[i].domid); | |
853d0289 | 339 | gnttab_set_unmap_op(&map->kunmap_ops[i], address, |
bce21a2b | 340 | flags, INVALID_GRANT_HANDLE); |
0930bba6 | 341 | } |
aab8f11a | 342 | } |
ab31523c GH |
343 | |
344 | pr_debug("map %d+%d\n", map->index, map->count); | |
36caa3fe JB |
345 | err = gnttab_map_refs(map->map_ops, map->kmap_ops, map->pages, |
346 | map->count); | |
ab31523c GH |
347 | |
348 | for (i = 0; i < map->count; i++) { | |
ebee0eab JB |
349 | if (map->map_ops[i].status == GNTST_okay) |
350 | map->unmap_ops[i].handle = map->map_ops[i].handle; | |
351 | else if (!err) | |
ab31523c | 352 | err = -EINVAL; |
853d0289 | 353 | |
dbe52836 JB |
354 | if (map->flags & GNTMAP_device_map) |
355 | map->unmap_ops[i].dev_bus_addr = map->map_ops[i].dev_bus_addr; | |
356 | ||
ebee0eab JB |
357 | if (use_ptemod) { |
358 | if (map->kmap_ops[i].status == GNTST_okay) | |
359 | map->kunmap_ops[i].handle = map->kmap_ops[i].handle; | |
360 | else if (!err) | |
361 | err = -EINVAL; | |
362 | } | |
ab31523c GH |
363 | } |
364 | return err; | |
365 | } | |
366 | ||
1d314567 OA |
367 | static int __unmap_grant_pages(struct gntdev_grant_map *map, int offset, |
368 | int pages) | |
ab31523c GH |
369 | { |
370 | int i, err = 0; | |
74528225 | 371 | struct gntab_unmap_queue_data unmap_data; |
ab31523c | 372 | |
bdc612dc DDG |
373 | if (map->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) { |
374 | int pgno = (map->notify.addr >> PAGE_SHIFT); | |
1affa98d DDG |
375 | if (pgno >= offset && pgno < offset + pages) { |
376 | /* No need for kmap, pages are in lowmem */ | |
377 | uint8_t *tmp = pfn_to_kaddr(page_to_pfn(map->pages[pgno])); | |
bdc612dc | 378 | tmp[map->notify.addr & (PAGE_SIZE-1)] = 0; |
bdc612dc DDG |
379 | map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE; |
380 | } | |
381 | } | |
382 | ||
74528225 JH |
383 | unmap_data.unmap_ops = map->unmap_ops + offset; |
384 | unmap_data.kunmap_ops = use_ptemod ? map->kunmap_ops + offset : NULL; | |
385 | unmap_data.pages = map->pages + offset; | |
386 | unmap_data.count = pages; | |
387 | ||
b44166cd BL |
388 | err = gnttab_unmap_refs_sync(&unmap_data); |
389 | if (err) | |
390 | return err; | |
ab31523c GH |
391 | |
392 | for (i = 0; i < pages; i++) { | |
393 | if (map->unmap_ops[offset+i].status) | |
394 | err = -EINVAL; | |
77c35acb DDG |
395 | pr_debug("unmap handle=%d st=%d\n", |
396 | map->unmap_ops[offset+i].handle, | |
397 | map->unmap_ops[offset+i].status); | |
bce21a2b | 398 | map->unmap_ops[offset+i].handle = INVALID_GRANT_HANDLE; |
ab31523c GH |
399 | } |
400 | return err; | |
401 | } | |
402 | ||
1d314567 OA |
403 | static int unmap_grant_pages(struct gntdev_grant_map *map, int offset, |
404 | int pages) | |
b57c1869 DDG |
405 | { |
406 | int range, err = 0; | |
407 | ||
408 | pr_debug("unmap %d+%d [%d+%d]\n", map->index, map->count, offset, pages); | |
409 | ||
410 | /* It is possible the requested range will have a "hole" where we | |
411 | * already unmapped some of the grants. Only unmap valid ranges. | |
412 | */ | |
413 | while (pages && !err) { | |
bce21a2b JB |
414 | while (pages && |
415 | map->unmap_ops[offset].handle == INVALID_GRANT_HANDLE) { | |
b57c1869 DDG |
416 | offset++; |
417 | pages--; | |
418 | } | |
419 | range = 0; | |
420 | while (range < pages) { | |
bce21a2b JB |
421 | if (map->unmap_ops[offset + range].handle == |
422 | INVALID_GRANT_HANDLE) | |
b57c1869 | 423 | break; |
b57c1869 DDG |
424 | range++; |
425 | } | |
426 | err = __unmap_grant_pages(map, offset, range); | |
427 | offset += range; | |
428 | pages -= range; | |
429 | } | |
430 | ||
431 | return err; | |
432 | } | |
433 | ||
ab31523c GH |
434 | /* ------------------------------------------------------------------ */ |
435 | ||
d79647ae DDG |
436 | static void gntdev_vma_open(struct vm_area_struct *vma) |
437 | { | |
1d314567 | 438 | struct gntdev_grant_map *map = vma->vm_private_data; |
d79647ae DDG |
439 | |
440 | pr_debug("gntdev_vma_open %p\n", vma); | |
c5f7c5a9 | 441 | refcount_inc(&map->users); |
d79647ae DDG |
442 | } |
443 | ||
ab31523c GH |
444 | static void gntdev_vma_close(struct vm_area_struct *vma) |
445 | { | |
1d314567 | 446 | struct gntdev_grant_map *map = vma->vm_private_data; |
16a1d022 DDG |
447 | struct file *file = vma->vm_file; |
448 | struct gntdev_priv *priv = file->private_data; | |
ab31523c | 449 | |
d79647ae | 450 | pr_debug("gntdev_vma_close %p\n", vma); |
2512f298 | 451 | if (use_ptemod) { |
d3eeb1d7 JG |
452 | WARN_ON(map->vma != vma); |
453 | mmu_interval_notifier_remove(&map->notifier); | |
2512f298 | 454 | map->vma = NULL; |
2512f298 | 455 | } |
ab31523c | 456 | vma->vm_private_data = NULL; |
16a1d022 | 457 | gntdev_put_map(priv, map); |
ab31523c GH |
458 | } |
459 | ||
dab069c6 DV |
460 | static struct page *gntdev_vma_find_special_page(struct vm_area_struct *vma, |
461 | unsigned long addr) | |
462 | { | |
1d314567 | 463 | struct gntdev_grant_map *map = vma->vm_private_data; |
dab069c6 DV |
464 | |
465 | return map->pages[(addr - map->pages_vm_start) >> PAGE_SHIFT]; | |
466 | } | |
467 | ||
7cbea8dc | 468 | static const struct vm_operations_struct gntdev_vmops = { |
d79647ae | 469 | .open = gntdev_vma_open, |
ab31523c | 470 | .close = gntdev_vma_close, |
dab069c6 | 471 | .find_special_page = gntdev_vma_find_special_page, |
ab31523c GH |
472 | }; |
473 | ||
474 | /* ------------------------------------------------------------------ */ | |
475 | ||
d3eeb1d7 JG |
476 | static bool gntdev_invalidate(struct mmu_interval_notifier *mn, |
477 | const struct mmu_notifier_range *range, | |
478 | unsigned long cur_seq) | |
16a1d022 | 479 | { |
d3eeb1d7 JG |
480 | struct gntdev_grant_map *map = |
481 | container_of(mn, struct gntdev_grant_map, notifier); | |
16a1d022 DDG |
482 | unsigned long mstart, mend; |
483 | int err; | |
484 | ||
d3eeb1d7 JG |
485 | if (!mmu_notifier_range_blockable(range)) |
486 | return false; | |
58a57569 | 487 | |
d3eeb1d7 JG |
488 | /* |
489 | * If the VMA is split or otherwise changed the notifier is not | |
490 | * updated, but we don't want to process VA's outside the modified | |
491 | * VMA. FIXME: It would be much more understandable to just prevent | |
492 | * modifying the VMA in the first place. | |
493 | */ | |
494 | if (map->vma->vm_start >= range->end || | |
495 | map->vma->vm_end <= range->start) | |
496 | return true; | |
58a57569 | 497 | |
d3eeb1d7 JG |
498 | mstart = max(range->start, map->vma->vm_start); |
499 | mend = min(range->end, map->vma->vm_end); | |
16a1d022 DDG |
500 | pr_debug("map %d+%d (%lx %lx), range %lx %lx, mrange %lx %lx\n", |
501 | map->index, map->count, | |
502 | map->vma->vm_start, map->vma->vm_end, | |
d3eeb1d7 | 503 | range->start, range->end, mstart, mend); |
16a1d022 DDG |
504 | err = unmap_grant_pages(map, |
505 | (mstart - map->vma->vm_start) >> PAGE_SHIFT, | |
506 | (mend - mstart) >> PAGE_SHIFT); | |
507 | WARN_ON(err); | |
58a57569 | 508 | |
d3eeb1d7 | 509 | return true; |
ab31523c GH |
510 | } |
511 | ||
d3eeb1d7 JG |
512 | static const struct mmu_interval_notifier_ops gntdev_mmu_ops = { |
513 | .invalidate = gntdev_invalidate, | |
ab31523c GH |
514 | }; |
515 | ||
516 | /* ------------------------------------------------------------------ */ | |
517 | ||
518 | static int gntdev_open(struct inode *inode, struct file *flip) | |
519 | { | |
520 | struct gntdev_priv *priv; | |
ab31523c GH |
521 | |
522 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
523 | if (!priv) | |
524 | return -ENOMEM; | |
525 | ||
526 | INIT_LIST_HEAD(&priv->maps); | |
1401c00e | 527 | mutex_init(&priv->lock); |
ab31523c | 528 | |
932d6562 | 529 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
fa13e665 | 530 | priv->dmabuf_priv = gntdev_dmabuf_init(flip); |
932d6562 | 531 | if (IS_ERR(priv->dmabuf_priv)) { |
d41b26d8 | 532 | int ret = PTR_ERR(priv->dmabuf_priv); |
932d6562 | 533 | |
ab31523c GH |
534 | kfree(priv); |
535 | return ret; | |
536 | } | |
d41b26d8 | 537 | #endif |
ab31523c GH |
538 | |
539 | flip->private_data = priv; | |
975ef7ff OA |
540 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
541 | priv->dma_dev = gntdev_miscdev.this_device; | |
ee7f5225 | 542 | dma_coerce_mask_and_coherent(priv->dma_dev, DMA_BIT_MASK(64)); |
975ef7ff | 543 | #endif |
ab31523c GH |
544 | pr_debug("priv %p\n", priv); |
545 | ||
546 | return 0; | |
547 | } | |
548 | ||
549 | static int gntdev_release(struct inode *inode, struct file *flip) | |
550 | { | |
551 | struct gntdev_priv *priv = flip->private_data; | |
1d314567 | 552 | struct gntdev_grant_map *map; |
ab31523c GH |
553 | |
554 | pr_debug("priv %p\n", priv); | |
555 | ||
30b03d05 | 556 | mutex_lock(&priv->lock); |
ab31523c | 557 | while (!list_empty(&priv->maps)) { |
1d314567 OA |
558 | map = list_entry(priv->maps.next, |
559 | struct gntdev_grant_map, next); | |
68b025c8 | 560 | list_del(&map->next); |
16a1d022 | 561 | gntdev_put_map(NULL /* already removed */, map); |
ab31523c | 562 | } |
30b03d05 | 563 | mutex_unlock(&priv->lock); |
ab31523c | 564 | |
932d6562 OA |
565 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
566 | gntdev_dmabuf_fini(priv->dmabuf_priv); | |
567 | #endif | |
568 | ||
ab31523c GH |
569 | kfree(priv); |
570 | return 0; | |
571 | } | |
572 | ||
573 | static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv, | |
574 | struct ioctl_gntdev_map_grant_ref __user *u) | |
575 | { | |
576 | struct ioctl_gntdev_map_grant_ref op; | |
1d314567 | 577 | struct gntdev_grant_map *map; |
ab31523c GH |
578 | int err; |
579 | ||
580 | if (copy_from_user(&op, u, sizeof(op)) != 0) | |
581 | return -EFAULT; | |
582 | pr_debug("priv %p, add %d\n", priv, op.count); | |
3b06ac67 | 583 | if (unlikely(gntdev_test_page_count(op.count))) |
ab31523c | 584 | return -EINVAL; |
ab31523c GH |
585 | |
586 | err = -ENOMEM; | |
975ef7ff | 587 | map = gntdev_alloc_map(priv, op.count, 0 /* This is not a dma-buf. */); |
ab31523c GH |
588 | if (!map) |
589 | return err; | |
ef91082e | 590 | |
68b025c8 DDG |
591 | if (copy_from_user(map->grants, &u->refs, |
592 | sizeof(map->grants[0]) * op.count) != 0) { | |
16a1d022 DDG |
593 | gntdev_put_map(NULL, map); |
594 | return -EFAULT; | |
ef91082e DDG |
595 | } |
596 | ||
1401c00e | 597 | mutex_lock(&priv->lock); |
ab31523c GH |
598 | gntdev_add_map(priv, map); |
599 | op.index = map->index << PAGE_SHIFT; | |
1401c00e | 600 | mutex_unlock(&priv->lock); |
ab31523c | 601 | |
68b025c8 DDG |
602 | if (copy_to_user(u, &op, sizeof(op)) != 0) |
603 | return -EFAULT; | |
604 | ||
ab31523c GH |
605 | return 0; |
606 | } | |
607 | ||
608 | static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv, | |
609 | struct ioctl_gntdev_unmap_grant_ref __user *u) | |
610 | { | |
611 | struct ioctl_gntdev_unmap_grant_ref op; | |
1d314567 | 612 | struct gntdev_grant_map *map; |
ab31523c GH |
613 | int err = -ENOENT; |
614 | ||
615 | if (copy_from_user(&op, u, sizeof(op)) != 0) | |
616 | return -EFAULT; | |
617 | pr_debug("priv %p, del %d+%d\n", priv, (int)op.index, (int)op.count); | |
618 | ||
1401c00e | 619 | mutex_lock(&priv->lock); |
ab31523c | 620 | map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count); |
68b025c8 DDG |
621 | if (map) { |
622 | list_del(&map->next); | |
68b025c8 DDG |
623 | err = 0; |
624 | } | |
1401c00e | 625 | mutex_unlock(&priv->lock); |
1f1503ba | 626 | if (map) |
16a1d022 | 627 | gntdev_put_map(priv, map); |
ab31523c GH |
628 | return err; |
629 | } | |
630 | ||
631 | static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv, | |
632 | struct ioctl_gntdev_get_offset_for_vaddr __user *u) | |
633 | { | |
634 | struct ioctl_gntdev_get_offset_for_vaddr op; | |
a879211b | 635 | struct vm_area_struct *vma; |
1d314567 | 636 | struct gntdev_grant_map *map; |
2512f298 | 637 | int rv = -EINVAL; |
ab31523c GH |
638 | |
639 | if (copy_from_user(&op, u, sizeof(op)) != 0) | |
640 | return -EFAULT; | |
641 | pr_debug("priv %p, offset for vaddr %lx\n", priv, (unsigned long)op.vaddr); | |
642 | ||
d8ed45c5 | 643 | mmap_read_lock(current->mm); |
a879211b DDG |
644 | vma = find_vma(current->mm, op.vaddr); |
645 | if (!vma || vma->vm_ops != &gntdev_vmops) | |
2512f298 | 646 | goto out_unlock; |
a879211b DDG |
647 | |
648 | map = vma->vm_private_data; | |
649 | if (!map) | |
2512f298 | 650 | goto out_unlock; |
a879211b | 651 | |
ab31523c GH |
652 | op.offset = map->index << PAGE_SHIFT; |
653 | op.count = map->count; | |
2512f298 | 654 | rv = 0; |
ab31523c | 655 | |
2512f298 | 656 | out_unlock: |
d8ed45c5 | 657 | mmap_read_unlock(current->mm); |
2512f298 DDG |
658 | |
659 | if (rv == 0 && copy_to_user(u, &op, sizeof(op)) != 0) | |
ab31523c | 660 | return -EFAULT; |
2512f298 | 661 | return rv; |
ab31523c GH |
662 | } |
663 | ||
bdc612dc DDG |
664 | static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u) |
665 | { | |
666 | struct ioctl_gntdev_unmap_notify op; | |
1d314567 | 667 | struct gntdev_grant_map *map; |
bdc612dc | 668 | int rc; |
0cc678f8 | 669 | int out_flags; |
0102e4ef | 670 | evtchn_port_t out_event; |
bdc612dc DDG |
671 | |
672 | if (copy_from_user(&op, u, sizeof(op))) | |
673 | return -EFAULT; | |
674 | ||
675 | if (op.action & ~(UNMAP_NOTIFY_CLEAR_BYTE|UNMAP_NOTIFY_SEND_EVENT)) | |
676 | return -EINVAL; | |
677 | ||
0cc678f8 DDG |
678 | /* We need to grab a reference to the event channel we are going to use |
679 | * to send the notify before releasing the reference we may already have | |
680 | * (if someone has called this ioctl twice). This is required so that | |
681 | * it is possible to change the clear_byte part of the notification | |
682 | * without disturbing the event channel part, which may now be the last | |
683 | * reference to that event channel. | |
684 | */ | |
685 | if (op.action & UNMAP_NOTIFY_SEND_EVENT) { | |
686 | if (evtchn_get(op.event_channel_port)) | |
687 | return -EINVAL; | |
688 | } | |
689 | ||
690 | out_flags = op.action; | |
691 | out_event = op.event_channel_port; | |
692 | ||
1401c00e | 693 | mutex_lock(&priv->lock); |
bdc612dc DDG |
694 | |
695 | list_for_each_entry(map, &priv->maps, next) { | |
696 | uint64_t begin = map->index << PAGE_SHIFT; | |
697 | uint64_t end = (map->index + map->count) << PAGE_SHIFT; | |
698 | if (op.index >= begin && op.index < end) | |
699 | goto found; | |
700 | } | |
701 | rc = -ENOENT; | |
702 | goto unlock_out; | |
703 | ||
704 | found: | |
9960be97 DDG |
705 | if ((op.action & UNMAP_NOTIFY_CLEAR_BYTE) && |
706 | (map->flags & GNTMAP_readonly)) { | |
707 | rc = -EINVAL; | |
708 | goto unlock_out; | |
709 | } | |
710 | ||
0cc678f8 DDG |
711 | out_flags = map->notify.flags; |
712 | out_event = map->notify.event; | |
713 | ||
bdc612dc DDG |
714 | map->notify.flags = op.action; |
715 | map->notify.addr = op.index - (map->index << PAGE_SHIFT); | |
716 | map->notify.event = op.event_channel_port; | |
0cc678f8 | 717 | |
bdc612dc | 718 | rc = 0; |
0cc678f8 | 719 | |
bdc612dc | 720 | unlock_out: |
1401c00e | 721 | mutex_unlock(&priv->lock); |
0cc678f8 DDG |
722 | |
723 | /* Drop the reference to the event channel we did not save in the map */ | |
724 | if (out_flags & UNMAP_NOTIFY_SEND_EVENT) | |
725 | evtchn_put(out_event); | |
726 | ||
bdc612dc DDG |
727 | return rc; |
728 | } | |
729 | ||
36ae220a | 730 | #define GNTDEV_COPY_BATCH 16 |
a4cdb556 DV |
731 | |
732 | struct gntdev_copy_batch { | |
733 | struct gnttab_copy ops[GNTDEV_COPY_BATCH]; | |
734 | struct page *pages[GNTDEV_COPY_BATCH]; | |
735 | s16 __user *status[GNTDEV_COPY_BATCH]; | |
736 | unsigned int nr_ops; | |
737 | unsigned int nr_pages; | |
77905584 | 738 | bool writeable; |
a4cdb556 DV |
739 | }; |
740 | ||
741 | static int gntdev_get_page(struct gntdev_copy_batch *batch, void __user *virt, | |
77905584 | 742 | unsigned long *gfn) |
a4cdb556 DV |
743 | { |
744 | unsigned long addr = (unsigned long)virt; | |
745 | struct page *page; | |
746 | unsigned long xen_pfn; | |
747 | int ret; | |
748 | ||
d6bbc2ff | 749 | ret = pin_user_pages_fast(addr, 1, batch->writeable ? FOLL_WRITE : 0, &page); |
a4cdb556 DV |
750 | if (ret < 0) |
751 | return ret; | |
752 | ||
753 | batch->pages[batch->nr_pages++] = page; | |
754 | ||
755 | xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(addr & ~PAGE_MASK); | |
756 | *gfn = pfn_to_gfn(xen_pfn); | |
757 | ||
758 | return 0; | |
759 | } | |
760 | ||
761 | static void gntdev_put_pages(struct gntdev_copy_batch *batch) | |
762 | { | |
d6bbc2ff | 763 | unpin_user_pages_dirty_lock(batch->pages, batch->nr_pages, batch->writeable); |
a4cdb556 | 764 | batch->nr_pages = 0; |
77905584 | 765 | batch->writeable = false; |
a4cdb556 DV |
766 | } |
767 | ||
768 | static int gntdev_copy(struct gntdev_copy_batch *batch) | |
769 | { | |
770 | unsigned int i; | |
771 | ||
772 | gnttab_batch_copy(batch->ops, batch->nr_ops); | |
773 | gntdev_put_pages(batch); | |
774 | ||
775 | /* | |
776 | * For each completed op, update the status if the op failed | |
777 | * and all previous ops for the segment were successful. | |
778 | */ | |
779 | for (i = 0; i < batch->nr_ops; i++) { | |
780 | s16 status = batch->ops[i].status; | |
781 | s16 old_status; | |
782 | ||
783 | if (status == GNTST_okay) | |
784 | continue; | |
785 | ||
786 | if (__get_user(old_status, batch->status[i])) | |
787 | return -EFAULT; | |
788 | ||
789 | if (old_status != GNTST_okay) | |
790 | continue; | |
791 | ||
792 | if (__put_user(status, batch->status[i])) | |
793 | return -EFAULT; | |
794 | } | |
795 | ||
796 | batch->nr_ops = 0; | |
797 | return 0; | |
798 | } | |
799 | ||
800 | static int gntdev_grant_copy_seg(struct gntdev_copy_batch *batch, | |
801 | struct gntdev_grant_copy_segment *seg, | |
802 | s16 __user *status) | |
803 | { | |
804 | uint16_t copied = 0; | |
805 | ||
806 | /* | |
807 | * Disallow local -> local copies since there is only space in | |
808 | * batch->pages for one page per-op and this would be a very | |
809 | * expensive memcpy(). | |
810 | */ | |
811 | if (!(seg->flags & (GNTCOPY_source_gref | GNTCOPY_dest_gref))) | |
812 | return -EINVAL; | |
813 | ||
814 | /* Can't cross page if source/dest is a grant ref. */ | |
815 | if (seg->flags & GNTCOPY_source_gref) { | |
816 | if (seg->source.foreign.offset + seg->len > XEN_PAGE_SIZE) | |
817 | return -EINVAL; | |
818 | } | |
819 | if (seg->flags & GNTCOPY_dest_gref) { | |
820 | if (seg->dest.foreign.offset + seg->len > XEN_PAGE_SIZE) | |
821 | return -EINVAL; | |
822 | } | |
823 | ||
824 | if (put_user(GNTST_okay, status)) | |
825 | return -EFAULT; | |
826 | ||
827 | while (copied < seg->len) { | |
828 | struct gnttab_copy *op; | |
829 | void __user *virt; | |
830 | size_t len, off; | |
831 | unsigned long gfn; | |
832 | int ret; | |
833 | ||
834 | if (batch->nr_ops >= GNTDEV_COPY_BATCH) { | |
835 | ret = gntdev_copy(batch); | |
836 | if (ret < 0) | |
837 | return ret; | |
838 | } | |
839 | ||
840 | len = seg->len - copied; | |
841 | ||
842 | op = &batch->ops[batch->nr_ops]; | |
843 | op->flags = 0; | |
844 | ||
845 | if (seg->flags & GNTCOPY_source_gref) { | |
846 | op->source.u.ref = seg->source.foreign.ref; | |
847 | op->source.domid = seg->source.foreign.domid; | |
848 | op->source.offset = seg->source.foreign.offset + copied; | |
849 | op->flags |= GNTCOPY_source_gref; | |
850 | } else { | |
851 | virt = seg->source.virt + copied; | |
852 | off = (unsigned long)virt & ~XEN_PAGE_MASK; | |
853 | len = min(len, (size_t)XEN_PAGE_SIZE - off); | |
77905584 | 854 | batch->writeable = false; |
a4cdb556 | 855 | |
77905584 | 856 | ret = gntdev_get_page(batch, virt, &gfn); |
a4cdb556 DV |
857 | if (ret < 0) |
858 | return ret; | |
859 | ||
860 | op->source.u.gmfn = gfn; | |
861 | op->source.domid = DOMID_SELF; | |
862 | op->source.offset = off; | |
863 | } | |
864 | ||
865 | if (seg->flags & GNTCOPY_dest_gref) { | |
866 | op->dest.u.ref = seg->dest.foreign.ref; | |
867 | op->dest.domid = seg->dest.foreign.domid; | |
868 | op->dest.offset = seg->dest.foreign.offset + copied; | |
869 | op->flags |= GNTCOPY_dest_gref; | |
870 | } else { | |
871 | virt = seg->dest.virt + copied; | |
872 | off = (unsigned long)virt & ~XEN_PAGE_MASK; | |
873 | len = min(len, (size_t)XEN_PAGE_SIZE - off); | |
77905584 | 874 | batch->writeable = true; |
a4cdb556 | 875 | |
77905584 | 876 | ret = gntdev_get_page(batch, virt, &gfn); |
a4cdb556 DV |
877 | if (ret < 0) |
878 | return ret; | |
879 | ||
880 | op->dest.u.gmfn = gfn; | |
881 | op->dest.domid = DOMID_SELF; | |
882 | op->dest.offset = off; | |
883 | } | |
884 | ||
885 | op->len = len; | |
886 | copied += len; | |
887 | ||
888 | batch->status[batch->nr_ops] = status; | |
889 | batch->nr_ops++; | |
890 | } | |
891 | ||
892 | return 0; | |
893 | } | |
894 | ||
895 | static long gntdev_ioctl_grant_copy(struct gntdev_priv *priv, void __user *u) | |
896 | { | |
897 | struct ioctl_gntdev_grant_copy copy; | |
898 | struct gntdev_copy_batch batch; | |
899 | unsigned int i; | |
900 | int ret = 0; | |
901 | ||
902 | if (copy_from_user(©, u, sizeof(copy))) | |
903 | return -EFAULT; | |
904 | ||
905 | batch.nr_ops = 0; | |
906 | batch.nr_pages = 0; | |
907 | ||
908 | for (i = 0; i < copy.count; i++) { | |
909 | struct gntdev_grant_copy_segment seg; | |
910 | ||
911 | if (copy_from_user(&seg, ©.segments[i], sizeof(seg))) { | |
912 | ret = -EFAULT; | |
913 | goto out; | |
914 | } | |
915 | ||
916 | ret = gntdev_grant_copy_seg(&batch, &seg, ©.segments[i].status); | |
917 | if (ret < 0) | |
918 | goto out; | |
919 | ||
920 | cond_resched(); | |
921 | } | |
922 | if (batch.nr_ops) | |
923 | ret = gntdev_copy(&batch); | |
924 | return ret; | |
925 | ||
926 | out: | |
927 | gntdev_put_pages(&batch); | |
928 | return ret; | |
929 | } | |
930 | ||
ab31523c GH |
931 | static long gntdev_ioctl(struct file *flip, |
932 | unsigned int cmd, unsigned long arg) | |
933 | { | |
934 | struct gntdev_priv *priv = flip->private_data; | |
935 | void __user *ptr = (void __user *)arg; | |
936 | ||
937 | switch (cmd) { | |
938 | case IOCTL_GNTDEV_MAP_GRANT_REF: | |
939 | return gntdev_ioctl_map_grant_ref(priv, ptr); | |
940 | ||
941 | case IOCTL_GNTDEV_UNMAP_GRANT_REF: | |
942 | return gntdev_ioctl_unmap_grant_ref(priv, ptr); | |
943 | ||
944 | case IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR: | |
945 | return gntdev_ioctl_get_offset_for_vaddr(priv, ptr); | |
946 | ||
bdc612dc DDG |
947 | case IOCTL_GNTDEV_SET_UNMAP_NOTIFY: |
948 | return gntdev_ioctl_notify(priv, ptr); | |
949 | ||
a4cdb556 DV |
950 | case IOCTL_GNTDEV_GRANT_COPY: |
951 | return gntdev_ioctl_grant_copy(priv, ptr); | |
952 | ||
932d6562 OA |
953 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
954 | case IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS: | |
955 | return gntdev_ioctl_dmabuf_exp_from_refs(priv, use_ptemod, ptr); | |
956 | ||
957 | case IOCTL_GNTDEV_DMABUF_EXP_WAIT_RELEASED: | |
958 | return gntdev_ioctl_dmabuf_exp_wait_released(priv, ptr); | |
959 | ||
960 | case IOCTL_GNTDEV_DMABUF_IMP_TO_REFS: | |
961 | return gntdev_ioctl_dmabuf_imp_to_refs(priv, ptr); | |
962 | ||
963 | case IOCTL_GNTDEV_DMABUF_IMP_RELEASE: | |
964 | return gntdev_ioctl_dmabuf_imp_release(priv, ptr); | |
965 | #endif | |
966 | ||
ab31523c GH |
967 | default: |
968 | pr_debug("priv %p, unknown cmd %x\n", priv, cmd); | |
969 | return -ENOIOCTLCMD; | |
970 | } | |
971 | ||
972 | return 0; | |
973 | } | |
974 | ||
975 | static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) | |
976 | { | |
977 | struct gntdev_priv *priv = flip->private_data; | |
978 | int index = vma->vm_pgoff; | |
c7ebf9d9 | 979 | int count = vma_pages(vma); |
1d314567 | 980 | struct gntdev_grant_map *map; |
df9bde01 | 981 | int err = -EINVAL; |
ab31523c GH |
982 | |
983 | if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED)) | |
984 | return -EINVAL; | |
985 | ||
986 | pr_debug("map %d+%d at %lx (pgoff %lx)\n", | |
987 | index, count, vma->vm_start, vma->vm_pgoff); | |
988 | ||
1401c00e | 989 | mutex_lock(&priv->lock); |
ab31523c GH |
990 | map = gntdev_find_map_index(priv, index, count); |
991 | if (!map) | |
992 | goto unlock_out; | |
aab8f11a | 993 | if (use_ptemod && map->vma) |
ab31523c | 994 | goto unlock_out; |
c5f7c5a9 | 995 | refcount_inc(&map->users); |
68b025c8 | 996 | |
ab31523c GH |
997 | vma->vm_ops = &gntdev_vmops; |
998 | ||
30faaafd | 999 | vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP | VM_MIXEDMAP; |
d79647ae DDG |
1000 | |
1001 | if (use_ptemod) | |
e8e937be | 1002 | vma->vm_flags |= VM_DONTCOPY; |
ab31523c GH |
1003 | |
1004 | vma->vm_private_data = map; | |
12996fc3 DDG |
1005 | if (map->flags) { |
1006 | if ((vma->vm_flags & VM_WRITE) && | |
1007 | (map->flags & GNTMAP_readonly)) | |
a93e20a8 | 1008 | goto out_unlock_put; |
12996fc3 DDG |
1009 | } else { |
1010 | map->flags = GNTMAP_host_map; | |
1011 | if (!(vma->vm_flags & VM_WRITE)) | |
1012 | map->flags |= GNTMAP_readonly; | |
1013 | } | |
ab31523c | 1014 | |
d3eeb1d7 JG |
1015 | if (use_ptemod) { |
1016 | map->vma = vma; | |
1017 | err = mmu_interval_notifier_insert_locked( | |
1018 | &map->notifier, vma->vm_mm, vma->vm_start, | |
1019 | vma->vm_end - vma->vm_start, &gntdev_mmu_ops); | |
1020 | if (err) | |
1021 | goto out_unlock_put; | |
1022 | } | |
1401c00e | 1023 | mutex_unlock(&priv->lock); |
f0a70c88 | 1024 | |
aab8f11a | 1025 | if (use_ptemod) { |
92937241 BO |
1026 | /* |
1027 | * gntdev takes the address of the PTE in find_grant_ptes() and | |
1028 | * passes it to the hypervisor in gntdev_map_grant_pages(). The | |
1029 | * purpose of the notifier is to prevent the hypervisor pointer | |
1030 | * to the PTE from going stale. | |
1031 | * | |
1032 | * Since this vma's mappings can't be touched without the | |
c1e8d7c6 | 1033 | * mmap_lock, and we are holding it now, there is no need for |
92937241 BO |
1034 | * the notifier_range locking pattern. |
1035 | */ | |
1036 | mmu_interval_read_begin(&map->notifier); | |
1037 | ||
298d275d | 1038 | map->pages_vm_start = vma->vm_start; |
aab8f11a DDG |
1039 | err = apply_to_page_range(vma->vm_mm, vma->vm_start, |
1040 | vma->vm_end - vma->vm_start, | |
1041 | find_grant_ptes, map); | |
1042 | if (err) { | |
283c0972 | 1043 | pr_warn("find_grant_ptes() failure.\n"); |
90b6f305 | 1044 | goto out_put_map; |
aab8f11a | 1045 | } |
ab31523c GH |
1046 | } |
1047 | ||
1d314567 | 1048 | err = gntdev_map_grant_pages(map); |
90b6f305 DDG |
1049 | if (err) |
1050 | goto out_put_map; | |
f0a70c88 | 1051 | |
aab8f11a | 1052 | if (!use_ptemod) { |
8d1502f6 | 1053 | err = vm_map_pages_zero(vma, map->pages, map->count); |
df9bde01 SJ |
1054 | if (err) |
1055 | goto out_put_map; | |
923b2919 DV |
1056 | } else { |
1057 | #ifdef CONFIG_X86 | |
1058 | /* | |
1059 | * If the PTEs were not made special by the grant map | |
1060 | * hypercall, do so here. | |
1061 | * | |
1062 | * This is racy since the mapping is already visible | |
1063 | * to userspace but userspace should be well-behaved | |
1064 | * enough to not touch it until the mmap() call | |
1065 | * returns. | |
1066 | */ | |
1067 | if (!xen_feature(XENFEAT_gnttab_map_avail_bits)) { | |
1068 | apply_to_page_range(vma->vm_mm, vma->vm_start, | |
1069 | vma->vm_end - vma->vm_start, | |
1070 | set_grant_ptes_as_special, NULL); | |
1071 | } | |
1072 | #endif | |
aab8f11a DDG |
1073 | } |
1074 | ||
f0a70c88 DDG |
1075 | return 0; |
1076 | ||
ab31523c | 1077 | unlock_out: |
1401c00e | 1078 | mutex_unlock(&priv->lock); |
ab31523c | 1079 | return err; |
90b6f305 | 1080 | |
a93e20a8 | 1081 | out_unlock_put: |
1401c00e | 1082 | mutex_unlock(&priv->lock); |
90b6f305 | 1083 | out_put_map: |
cf2acf66 | 1084 | if (use_ptemod) { |
cf2acf66 | 1085 | unmap_grant_pages(map, 0, map->count); |
d3eeb1d7 JG |
1086 | if (map->vma) { |
1087 | mmu_interval_notifier_remove(&map->notifier); | |
1088 | map->vma = NULL; | |
1089 | } | |
cf2acf66 | 1090 | } |
16a1d022 | 1091 | gntdev_put_map(priv, map); |
90b6f305 | 1092 | return err; |
ab31523c GH |
1093 | } |
1094 | ||
1095 | static const struct file_operations gntdev_fops = { | |
1096 | .owner = THIS_MODULE, | |
1097 | .open = gntdev_open, | |
1098 | .release = gntdev_release, | |
1099 | .mmap = gntdev_mmap, | |
1100 | .unlocked_ioctl = gntdev_ioctl | |
1101 | }; | |
1102 | ||
1103 | static struct miscdevice gntdev_miscdev = { | |
1104 | .minor = MISC_DYNAMIC_MINOR, | |
1105 | .name = "xen/gntdev", | |
1106 | .fops = &gntdev_fops, | |
1107 | }; | |
1108 | ||
1109 | /* ------------------------------------------------------------------ */ | |
1110 | ||
1111 | static int __init gntdev_init(void) | |
1112 | { | |
1113 | int err; | |
1114 | ||
1115 | if (!xen_domain()) | |
1116 | return -ENODEV; | |
1117 | ||
6926f6d6 | 1118 | use_ptemod = !xen_feature(XENFEAT_auto_translated_physmap); |
aab8f11a | 1119 | |
ab31523c GH |
1120 | err = misc_register(&gntdev_miscdev); |
1121 | if (err != 0) { | |
283c0972 | 1122 | pr_err("Could not register gntdev device\n"); |
ab31523c GH |
1123 | return err; |
1124 | } | |
1125 | return 0; | |
1126 | } | |
1127 | ||
1128 | static void __exit gntdev_exit(void) | |
1129 | { | |
1130 | misc_deregister(&gntdev_miscdev); | |
1131 | } | |
1132 | ||
1133 | module_init(gntdev_init); | |
1134 | module_exit(gntdev_exit); | |
1135 | ||
1136 | /* ------------------------------------------------------------------ */ |